Costa Rica

Medicinal gardens, cacao and longevity

Evidence at a glance

Scope: Botanical traditions and human research relevant to Costa Rica. Evidence types: Ethnobotanical reports, observational studies, clinical trials or safety assessments where cited. Cancer control: No demonstrated cure from the traditional-use records summarized here. Limitation: Selective source review, not a systematic review.

Cacao: the plant and the trial are different stories

The 2022 COSMOS trial enrolled 21,442 older US adults—women at least 65 and men at least 60. It compared capsules supplying 500 mg of cocoa flavanols daily, including 80 mg of epicatechin, with placebo. Over a median 3.6 years, total cardiovascular events occurred in 410 versus 456 participants: hazard ratio 0.90, 95% confidence interval 0.78–1.02. The primary result did not establish a reduction.

Nicoya: longevity without a single “secret”

A 2023 analysis used records covering about 550,000 adult Costa Ricans during 1990–2020. Nicoyan men born in 1905 had 33% lower adult mortality than other Costa Rican men; those born in 1945 had 10% higher mortality. The geographic area with unusually low older-adult mortality had also contracted.

Guanábana: a cancer claim that needs a boundary

A 2017 randomized study enrolled 30 people with colorectal cancer after removal of the primary tumor; 28 completed eight weeks of leaf extract or placebo. Researchers tested patients’ serum against cancer cell lines and reported greater laboratory cytotoxicity with supplementation. That is not evidence that tumors shrank or that recurrence or survival improved.

An EU-FORA risk assessment published in EFSA Journal in 2020 examined safety concerns surrounding Annona preparations, including potential neurotoxicity. Fruit, tea and concentrated extracts should not be treated as equivalent products.

Clinical interpretation and safety

Documented traditional use does not establish treatment efficacy. Extracts, infusions, foods, and isolated compounds are different interventions. Laboratory cytotoxicity is not clinical tumor control. Review supplements and interactions with the treating team; do not substitute unverified products for established cancer care.

Sources: Primary references linked in the evidence sections above. Last chapter edit: October 18, 2026. Evidence scope: selective, not exhaustive. Evidence Explorer · Methods.